Drier for evaporating fruits, vegetables, and the like.



H. L. SHEPARD.

DRIER FOR EVAPORATING FRUITS, VEGETABLES, AND THE LIKE.

APPLICATION FILED JUNE 29. 1917.

1,300,497. Patented Apr. 15, 1919.

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H. L. SHEPARD. DRIER FOR EVAPORATING FRUITS, VEGETABLES, AND THE LIKE.

APPLICATION F LED JUNE 29. I917.

Patented Apr. 1919.

3 SHEETS-SHEET 2 H. L. SHEPARD.

APPLICATION FILED JUNE 29. I917- Patented Apr. 15, 1919.

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m L. snnrann, or ron'rrann, OREGON, AssI 'Non' T0 racrrrc EVAPORATOB comm, or ron'rmmn, OREGON, A conroaarrorror onneon.

DRIER FOB EVAPORATING FRUITS, VEGETABLES, AND THE Specification of Letters Patent. Patented Apr. 15, 1 919.

Application filed June 29,1917. Serial No. 177,722.

This invention relates to driers for evaporating fruits, vegetables and the like and consists in certain improvements therein as will be hereinafter fully described and pointed out in the claims.

In evaporating fruits, vegetables and similar materials it is desirable to subject each particle of the material to a like amount of air of like quality so that the drying may be uniform. Further the drying must be. sufiiciently rapid to prevent molding but not I so rapid as to seal the materials against the evaporation of moisture. This can best be attained by subjecting all the surfaces to a like impact of air so that there is an equal evaporation from all surfaces. I This has been accomplished by' shifting the material beingtreated so as to present difi'erent sur faces to the air but this has required a great deal of labor and has of necessity made the intervals of change infrequent. In the present invention this variation in the direction of air is accomplished by reversing the flow of air through the chamber. Other details of the invention will appear from the specification and claims.

The invention is illustrated in theaccompanying drawings as follows I Figure 1 shows a sectionimmediately below the floor of the drying plant illustrating the system of ducts for conveyingthe air to the different parts of the plant.

Fig. 2 shows a horizontal section through the drying'chambers on the line 2-2 in Fig. 5.

Fig. 3 shows part-of the chamber on the lines 3-3 in Figs. 1 and 2.

Fig. 4 shows a plan view of'one of the tray racks with a tray in place.

Fig. 5 shows "a section on the lines 5-5 inFigs.1and2. r

1 marks the second main drying chamber and 2 the first main drying chamber. The chamber 1- has the tracks 3 and 4 running lengthwise through it and the chamber 2 has the tracks 5 and 6 running lengthwise through it. An air lock 7 is arranged at one end of the chambers. Turn tables 9, 10, 11

and 12 are arranged at one end of each of the tracks 3, 4, 5 and 6 respectively and connect the tracks with a track 8 extending through the air lock. Through the means of these turn tables and'tracks which are-of common construction the cars carrying. the racks can be moved from track to track and from chamber to chamber and reversed from one track to the other, if desired.

Doors 13 are arranged atthe openings in the air lockin the usual manner. An air lock 14 is arranged opposite the airlock 7.

This has a series of tracks 15, 16 and 17 which are'connected-by turn tables 18 and 1-9 with the tracks 3, 4, 5 and 6. By-meansxof these tracks in the air lock 'andthe turn tables, material may be. transferred from chamber to chamber and reversed if desired. The usual doors 20 are provided for closing the openings to the air lock.

Arranged along the opposite chamber 1 are the vertical ducts 21 and 22 and along the side of the chamber2 the vertical ducts 23 and 24. These ducts are arranged at intervals- Heating coils 25' and 26".

are provided, the heating coil 25 opening ides I of the into a duct 32 below the levelof the floor g of the dryingchamber and the heating coil 26 delivering to a duct 33. The air is drawn to theheater coils'25 and '26 from the ducts 27 and 28 respectively. Dampers 29 and 30 control the inflow to the ducts 27 and 2.8 and a damper 31 controls theconnection between the ducts 27 and 28. "The duct 32 connects with a duct 34 running along and below the side of the drying chamber. The vertical ducts 21 open into the duct 34. Y Aduct 35 .runs just below the opposite side of the drychamber '1- and .the vertical ducts 22 in the duct 38 and dampers 42 and 43 in the duct 39; An exhaust fan 44 is connected by a duct 45 with the duct -38 at a point between the gates or dampers 40 and 41 and a fan 46 is connected byv a duct 47 with the duct 39 between the gates 42 and 43. The fan 44 is driven from the motor 44 and the fan 46 by a motor 46. The fan 44 discharges through the duct 48 and the fan 46 through the duct 49 to a duct 50. The duct 50 has the discharge openings 51 and 52. Gates 5.3 and 54 control these openings. Gates 56 and-57 are also provided in the duct 50 at the opposite sides of the'openings 51 and 52'6from the gate and outside of the point of entrance of the passages 48 and 49 sothat by closing the gates 55, 56 and 57 and openin the gates 53 and 54 discharge may be ma e directly to the atmosphere but by closing the gates 53 and 54 and operating the gates 56 57 and 55 the exhaust air may be delivered in either direction through the duct .50.

The duct 50 communicates with the duct 58 which is a return'duct to the duct 27. By means of this the exhaust airhaving passed through the dry the heating coils 25 so as to be used a second time if desired. I

Thevertical passages 21, 22, 23 and 24 are divided by vertical plates so'as to form divisions 60, 61 and 62 as indicated in Fig. 5, each division being controlled by a gate 63. These divisions open into the drychambers at different levels. By adjusting the valves .or gates 63 an equal quantity of air may be delivered through each division if desired. The plates forming the divisions are bent in,-forming deflectors 64 so as to give to the air a horizontal direction as it is delivered to the chamber. These deflector plates have a portion with a downward inclination so as form.

the tracks in the drier.

to neutralize the tendency of the moving air to follow the upper portion of the division directly underthe deflector plate. 'By giving to the deflector plate this upward and then downward direction the air'is given a slight downward slant which makes the delivery from the opening to the drying chamber practically uniform throughout the different levels ofthe openings sothat there is a uniform flow of, air from top to bottom. :The vertical passages 21,22,23 and 24 are arranged at intervals along the sides of the I dry'1ng'chambers. It is desirable that the air be delivered uniformly throughout the length of the drying chamber. To accomplish this the .openings are flaring horizontally.- This is accomplished by plates 65 (see Fig. 2) and these plates extend from the openings and come together at a point be tween the openings. Asthe air leaves theopenings it expands following these plates so that the delivery to the chamber is uni- Cars 66 are arranged in trains or series on The racks 6,7 are built up on the cars so as to practically fill the dry chamber from top tobottom. The material is placed on the trays 68, these trays aving perforated? bottoms. The trays are p chamber may be returnedbyway of the duct 58 and through arranged with a slight incline so that the air passing horizontally will notonly pass between the trays but through the bottoms of dry chambers. It will be understoodthat this air is more or less moisture-laden but is usually still capable of taking up some mois ture. The duct 50 has the extension 0 which connects with a vertical duct 71. The

vertical duct 71 opens into what may be called a primary drying chamber 72. The

tracks 15, 16 and 17 extendinto this primary chamber. Ordinarily the side opposite theduct 71 will be open so that the exhaust air is directed across the chamber 72 and'discharged to the atmosphere. With some materials this preliminary treatment is quite eflective. v In theoperation of this drier and the application. of the process forming this invention the cars carrying the stacks of trays are arranged in the dry chambers. Ifthe cars are run through the different chambers thev succession is controlled by the kind of-material being treated. With some materialit is desirable to pass it through the primary drier. With other materials the pa'ssingof .the air through a second time by .way of the duct 58 may be desirable. With some mate]- rials the entire drying is accomplished in a single chamber and without change of the material in the chamber.

The material having been placed in chamber, as for instance, the chamber 1 and u the air given a passage from one sid'e'to the other, as for instance by the opening of the gates 32, closure of the gates '32", closure of the gates 40 and the opening of-the-gates '41, theair ispassed through thechamber for" an interval giving-thematerial facing theincoming air the efi'ect of the direct impact of the .air from the direction it is moving.

After this has proceeded a short time, the

gates 32 are closed, the gates 32 .opened,; "the gates 40 opened and-the gates 41 closed.

This reverses the direction of the flow of. air,

the air passing from the vertical passages l 22, across the chamber, down the vertical passages 21 and then out by theduct 34 through the fan. With this reversing of the" current at intervals the-impact of the air' is upon different portions of the fruit and this 'is accomplished without moving the stacks in the drier. As this reversal can be accom- .plished w'ith very little labor and promptly the intervals may be made, if desired,-; =:com-

paratively short so that the drying action air by the duct 58 to the heater 25. In this case the gates 29 and 31 should be closed and when this happens the air is simply circulated. If desired a certain amount may be discharged and a certain amount of fresh air taken in by partially opening the gate 53 and the gate 29,

The drying chamber 2 may be utilized in the same manner.. The air may be returned by way of the duct 58 closing andopening the gates so as to complete this passage b way of the 'duct 50, duct 58 and ducts 2% and 28.

Withg'some materials this uniform treatment' and frequent varying of the point of impact of the air upon the material results in a much more uniform and satisfactory product, than where it is attempted to dry the material with air passed in from one direction and the direction may be shifted with very 'much shorter intervals than where a changein the direction is attempted by shifting the material.

What is claimed as new is V 1. In a drier, the combination of a drying chamber; two sets of means for supporting material to be dried in said chamber;

means for directing a current of air through said chamber and at an angle to the material on said supports, the angles ofone set of supports being opposite to those of the other; and means for reversing the direction of flow of air through the chamber.

2. In a drier, the combination of a drying chamber; two sets of'trays arranged in'the chamber; means for directing a current of an through said chamber and at an angle to the tray bottoms and past both sets, t e

angles of the bottoms of one set being opposite to those of the other; and means for reversing the direction of flow of air through the chamber.

3. In a drier, the combination of a drying chamber; and vertical air ducts at intervals at the sides of the chamber, the front faces of the ducts being open to' the chamber, the openings from the ducts to the chamber flaring horizontally.

4. In a drier, the combination of a drying chamber; vertical air ducts at intervals at the sides of the chamber; vertical divisions in said ducts; .and deflectors for delivering the air from the different divisions at dif-.

ferent levels, said deflectors having a downward slant and giving a downward slant to a portion of the air deflected.

'5. In a drier, the combination of a drying chamber; vertical air ducts at intervals at the sides of the chamber, the front faces: of the ducts being'open to the chamber and the openings from the ducts to the chamber flaring horizontally; vertical divisions arranged insaid ducts; and divisions for discharging. the air from said vertical ducts atdifferent levels whereby the air is delivered uniformly throughout the chamber. V

6. In a drier, the combination of a drying chamber; a heater; means for directing a current of air through the heater and thenthrough said chamber; mechanism for varying the direction of the flow through the chamber; and devices for returning the air passed through the drying chamber to the means whereby the air is circulated, passing from the heater to the chamber and then is returned to the heater.

7. In a drier, the combination of two drying chambers; means for directing a current of air throughthe first of said chambers and; delivering the-air dischargedfrom the-first of said chambers to the second of said chambers; and means for reversing the flow of air through the first of said chambers.

*8. In a drier, the-combination of a drying chamber arrangedon one level; horizontal diicts on a different level; vertical ducts leading from the horizontal ducts to the side walls of the dryingchamber; and means directing a flow of air from the vertical ducts across the chamber. v

I 9. In a drier, the comblnatlon of a drying chamber arranged on one level; a heater arranged on another level from-the drying.

chamber;'horizontal ductslea'ding from the 1 heater, said horizontal ducts being arranged 7 below the drying chamber; vertical ducts leading from thehorizontal ducts to the side walls of the drying chamber; and means directing a flow of air from the vertical ducts across the chamber. v

, In testimony whereof I have hereunto set my hand.

HENRY L. SHEPARD. 

